Clamp



(No Model.)

' E. SHAW. GLAMBLV No. 360,974. PateAntvedApr. 12, 1887.'

WiINESSES: l MV1-imam j' UNITED STATES PATENT OEEICE.

` vwhich will enable those skilled in the art relat- EDGAR SHAW, OF LYNN, -ASSIGNOR, BY MESN E ASSIGNMENTS, TO THEISHAW' MANUFACTURING COMPANY, vOF BOSTON, MASSACHUSETTS.

CLAMP.

SPECIFICATION forming part of Letters Patent N o. 360,974, dated April 12, 1887.

Application filed November 10, 1885. Serial No. 182,398. (N o model.)

To all whom it may concern.-

Be it known that l, EDGAR SHAW, of Lynn, in the countyof VEssex and State of Massachusetts, vhave invented certain new and usefulImprovernents in Clamps, ot' which the following is a full, clear, and exact description,

ing thereto to make and use the same, reference being had to the accompanying drawings, forming a part of this specification.

The invention relates to that class of clamps that consist, generally, of a bar or beam provided with two clamping arms or jaws, one of said jaws carrying a clam ping-screw and being formed on or attached to the beam, and the other arm or jaw being carried upon a slide or yoke which is adapted to be moved along the beam and to be rmly locked thereon at any point by the application of the clamping-pressure to the jaw.

With these clamps. the locking of the movable slide with its attached jaw to thebeam has usually been accomplished by the arm or its slide engaging with notches or teeth on the beam. This methodisobjectionable, iirst, be-v faces have been provided with an adjustable jaw carried by a slide which was constructed' 'construction and operation in which the .ob-

jections referred to shall be obviated.

The invention consists of a beam-clamp in whiclfthe adjustable yoke or slide, carrying a clamping arm or jaw, is provided with ashoc, wedge, block, or similar device, which is seslide and is interposed between the jaw and the beam or between the slide and the beam,

cured to or held in operable position by the i which shoe, wedge, or block has on the side clamp. Fig. 2 represents a longitudinalsection of aportion thereof. Fig. 3 represents a side -elevation of another form otmy improved clamp,showing a wooden beam. Fig. 4 represents a section of the jaw and slide shown in Fig. 3. Fig. 5 represents a section on linexw, Fig. 3. Fig. 6 represents asection on line z e, Fig. l.

The same letters of referenceindicate the same parts in all the figures. A

In the drawings, a represents the beam or bar of a beam-clamp, which beam is constructed with plain or ilat upper and lowerA edges; and b represents an arm formed on or rigidly attached to the beam at one end.

c represents ascrew working in a tapped socket in the arm b, and having a clampingplate, c', at one end. l

d represents a slide or yoke, composed of two sides or ears at opposite sides ofthe beam and a connecting crosspiece bearing on the lower edge of the beam or on an interposed shoe, as the case may be. Said slide carries a jaw, f, which may be either rigidly attached to the slide, thus forming a part thereof, or pivoted thereto so as to be capable of rocking or oscillating on the slide.

- The lower end of the jaw fis over the upper edgeof the beam. When the jaw is attached to the slide so as to be capable of rocking independently, itis secured by a pivot, e, to ears at the upper ends of the sides of the slide, so that when pressure is exerted on the upper end of the jaw f in the direction indicated by the arrow in Fig. l a portion lof its lower end at one side of the pivot e is pressed downwardly on a shoe, j, interposed between the jaw and the upper edge of the beam c, and

IOO

at the saine time the portion of the slide d extending-across the flat lower edge of the beani is pressed upwardly against such edge or against the shoe underneath the beam, as the case may be. The slide and jaw are thus locked to the beam wholly by friction, so that they cannot be moved while pressure is applied to the upper end ot' the jaw, the beam being firmly grasped between the block or shoej and the lower portion of the slide, or between the block or shoe j and the shoe underneatli the beam, as the case may be.

The forni of the lower end of the jaw f, as also the forni of the shoe, may be variously modified. In Figs. 1 and 2 I have shown the jaw as extended and slightly curved and bearing on a wedge-shaped shoe, while in Figs. 3 and 4 it is substantially straight. Other modifications may be adopted without departing from the spirit of my invention.

The shoe, as shown in the drawings, is bent up in front of the lower innei end of the clamping-jaw, and this is for the purpose of holding the shoe in place between the jaw and the beam, as obviously, when the clamping arm orjaw is moved along the beam,it will be necessary that tlie shoe (at such time loosened f rom between the slide or jaw and the beam) be carried with it. Any other suitable means, however, niay be employed for thus lioldiug or securing the shoe or wedge in operable position between the slide and the beam or the jaw and the beam.

If preferred, the jaw f, when a pivoted one is used, may bear directly on the upper edge of the beam, instead of on a shoe interposed between the jaw and the beam. shoe, however, because it furnishes, when desited, a more extended clamping or friction surface than can be practically secured by the jaw without using the slioe,aiid also because it protects the edge of the beam from wear and may be renewed at slight expense when worn or broken.

Vhen the jaw fis mounted on the slide so as to be incapable of rocking, it may be east so as to form a part of the saine piece therewith; 0r it may be rigidly secured to the side pieces of the slide by bolts or screws. I prefer, however, to connect the jaw with the slide by means of the pivot e, as before described, and, if desired, to make it practically rigid by one or more set-screws, e', inserted in tapped orifices in the lower and rear portion of the jaw, so as to bear against the shoe j at one side of the pivot, or directly upon the upper edge of the beam in case the shoe be not used.

This construction also enables the slide to be adjusted to the depth of the beam, as may become desirable when the latter is made of wood and shrinkage occurs, or when wear of the same is to be compensated for.

A shoe or rocking plate, c, having a flat upper surface and provided with laterally-pro- 6 5 jeeting trunnions c, may be interposed between the lower cross-piece of the slide and the lower edge ofthe beam. The trunnions e" are rounded I prefer theand rest in ears or sockets e", formed inthe slide, so that the plate ez can rock slightly in the slide to conform to the beam and maintain an extended bearing on the lower edge of the same when the slide is tipped backwardly by pressure exerted against the jaw f. This rocking plateis available in any forni ofsuch clamp; but it will not usually be employed, except when the clamping-arm is rigid with the slide, orl when it is desired to construct the slide with a specially-extended or particularly-shaped locking-surface for the lower edge of the beam. Thus, if the clamping-arm be rigid with the slide, the best action is secured by using a shoe or plate on the lower edge of the beam as well as on the upper edge, as without such lower plate the pressure would be greatest at one end of the slide and the beam would be indented and roughened; but with the plate the pressure would be uniform throughout the length thereof, and undue wear upon the beam would be obviated. When the arm is pivoted to the slide, the upper shoe only will ordinarily be required, particularly with wooden beams, as the slide would be automatically adjusted so as to bear sufficiently even upon the under edge ofthe beam. In the case of metal beam-clamps, the strain they are subjected to and the unyieldiiig character oftheir beams require slides provided with extended loekingsuri'aces arranged to act iu the most efficient manner to lock thc slide to the beam, and to this end the rocking plate is used and either the upper or lower shoe or plate may be provided with a still more extended bearing-surface by recessing` the edge of the heani, as seen in Fig. 6, and shaping the shoe or plate to correspond thereto.

Iii Fig. 3 I have show n the construction which I use when the beam is made of wood. In this case the yoke of the fixed jaw I) is formed with a socket, b', in its lower portion to i'eceive the beam, and is secured to tliebeaiii by a wedgeshaped key, b2, driven in between the bottoni of the socket 7) and the lower edge of the beam.

Thejawf may be provided at its nppei end with pivoted wedge-sliaped plates l I, Fig. 8, or with a plate, my, having a hcmisplierical boss fitting in a socket in the jaw f, as shown in Fig. l. The jaw is thus adapted to hold articles of irregular shape, theplates lor m being adapted to assume various inclinations.

lVheii it is desired to move the adjustable clampiug-jawf, its upper end is pressed for ward to cause its lower end and the slide to release their hold on the beam,when the j aw and slide may be freely iiiovedou the beam. When the jaw f is adjusted and the article to be clamped is placed between the jaw and the plate c of the clamping-screw, the pressure effected by operating the screw causes the jaw and the slide or the interposed shoe and the slide to grasp the beam, the jaw being thus held as firmly as if it were rigidly attached to the beam.

Vhen the adjust-able jaw f is pivotcd to thc slide, I prefer to placea spring, s, under the forward portion of the jaw, as shown in Fig. 2, such spring normally pressing the j aw backf ward and causing the rear portion of its lower end to bear with a yieldingpressure on the shoe j, so that the jawf is normally in position to be instantly affected by the pressure exerted against it. This same purpose may be accomplished by a piece of rubber placed between the lower edge of the beam and the slide cl; but I prefer a spiral spring, as shown.

In the above constructions the hinged jaw by preference forms the top of the yoke or slide; but obviously the top of the slide may be otherwise constructed, and the j aw it carries may be rigidly or pivotally attached thereto in other ways than those herein shown or described. So, too, although the rigid clamping-arm-that is, the clamping-arm formed on or attached to the bar or beam-has been herein described as carrying the clampingscrew, this screw may be carried upon the arm which is carried upon the adjustable slide. Furthermore, I anticipate that itis possible to use the rocking gib or shoe upon the top of the beam as well as upon its lower edge, or both.

It will be seen that by my improvements I am enabled quickly to slide the movable jaw f to any desired point on the beam and effectively to lock it thereto by friction only, and all liability of said jaw slipping on the beam or of injury thereto by the clamping operation is avoided.

Having now fully described my invention, what I claim, and desire to secure by Letters Patent, is- Y 1. In a beam-clamp, the combination of the beam, anadj ustable slide adapted to be moved along the beam and provided with a clamping arm or jaw, and a shoe which is secured to the slide and interposed Vbetween the slide and the beam, substantially as set forth.

2. In a beam-clamp, the combination of the beam, an adjustable slide adapted to be moved along the beam and provided with a clamping arm or jaw, and a shoe which is secured to the clamping-arm and is interposed between the arm and the beam, substantially as set forth.

3. In a beam-clamp, the combination of the beam, a slide adapted to be'moved along the beam and earryiugaclamping arm or jaw, and

a rocking plate pivotally supported on the slide and bearing against the beam, substan-A tially as set forth.

4. In a/beam-clamp, the combination, with the beam, of a slide which is adapted to be moved along the beam, and which carries a clamping-jaw pivoted to said slide, the lower end of said jaw beingl over the upper edge of the beam, substantially as set forth.

5l. In a beam-clamp, the combination, with the beam, of a slide which is adapted to be -moved along the beam, a clamping-jaw pivoted to and carried upon said slide, and a block or shoe interposed between the lower entL of the jaw and the upper edge of the beam, substantially as set forth.

6. In a beam-clamp, the combination of the beam, a slide adapted to be moved thereon, a jaw pivoted to and carried upon said slide, a shoe interposed between the beam and the jaw, and a spring arranged to hold the jaw normally in operative position, substantially as set forth.

7. In a beam-clamp, the combination, with the beam, of a slide adapted to be moved along the beam and carrying a clamping arm or j aw, a block or shoe interposed between the upper edge of the beam and the jaw, and a rocking plate or shoe pivotally supported on the slide and bearing against the lower edge of the beam, all substantially as set forth.

8. In a beam-clamp, the combination of a clamping-jaw which is pivotally attached to a slide, which slide is adapted to be moved along the beam, a shoe or wedge interposed between said pivoted jaw and the beam, and a set-screw, e', passing down through the lower and rear part of said jaw, and adapted to limit, or, if desirable, entirely to prevent, the backward motion of the pivoted jaw, substantially as set forth.

In testimony whereof I have signed my name to this specification, in the presence of two subscribing witnesses, this 5th day of November, 1885.

EDGAR SHAV.

Vitnesses:

C. F. BROWN, H. BROWN. 

